Method and apparatus for appendaging pottery ware



Oct. 29, 1946.

METHOD f l l 2 Sheets-Sheet l WILLIAM J.' MILLER ASHLEY J. REEK BY Oct'. 29, `1946. w. J. MILLER r-:T AL

2,410,123 METHOD AND APPARATUS FOR APPENDAGING POTTERYWARE 2 Sheets-Sheet 2 Filed Jan. 27, 1943 IN'VENToRxi.4 WILL/AM d. MILLER YSH'LEY d. REEK 700m TORZE/ Patented Oct. 29, Y1946 ivmrnop `AND APPARATUS Fon Arl?ENDAGI,NGy POTTERY TARE William J. Miller, swissvale, and Ashley J'. Reek, Carrick, Pa., assgnors to Miller Pottery Engineerng Company,` Svvssvale, Pa., a corporation of Pennsylvania Applicata@ January 27, 1943, serial No. 473,670

This is a continuation in part of our coepending application Serial No. 392,276, filed rMay '7, 1941, and it has to do with apparatus for ap.

pendaging pottery ware, particularly the mold which is employed to form the appendage.

More particularly, the present invention has to do with the sprue or that portion of the solidified material which remains in the fillingopening after the appendage has set up and the problem of removal from the remainder of the appendage without tearing out material forming the appendage. The object is to obtain a clean Abreak close to the surface of the appendage requiring little or no sponging or fettling to remove the traces thereof. l I Y l In the drawings:

Fig. 1 is a view showing a casting unit With the rear mold section removed illustrating how the appendageis 'cast and united to the prefabricated ware.

Fig. 2 is a fragmentary section showing the restricted passage between the mold cavity and the lling opening.

Fig. 3 is a fragmentary section looking down onl top of the restricted passage of Fig. 2.

Fig. 4 is an elevation of a -mold half illustrating:

another form of iilling opening.

Fig. 5 is a sectional elevation through ther center of the mold with the two halves in closed relation. f

Fig. 6 is anenlarged sectional View showing the slit. I

Fig. A'l is a sectional View illustrating the iinlike juncture between the spr-ue and the appendage.

Fig. 8 shows how the sprue of Fig. 7 is broken away from the appendage.

Fig. 9 is a plan view of a mold section and rigid hinge plate on which the same is mounted.A

Fig. 10 is an elevation of one section of a partible mold showing a modified form of pouring hole and gate.

Fig. 111s a topplan viewof the complete mold, of which one section is illustrated in Fig. 10.

Fig. 12jis a fragmentary View showing how the; gate may be filleted to avoid'the production of al 4 Claims. (Cl. 25-129) toured ware receiving surface. 5, Fig. 9', of a partible mold, Figs. 1 2 and 3, in leakproof sealed relation. The partible mold which comprisesl two mating sections 6 and 6a is hingedly mounted on a hinge pin 'I and is opened and closed me-.

chanically in the manner described in our copending application. Fluid slip is fed to. the, mold through a rubber nozzle 8 fitted into a pipe the'appendage shrinks and solidies. Since the flow of slip through the outlet I5 of the molding cavity is blockedby the ware, the appendage becomes attached to the ware as it solidies,y a permanent bond ofhigh mechanical strength being formed.l

sharp edge at the juncture of the sprue with the appendage.

With reference to Fig. 1, an appendage casting unit is shown which includes a base AI and a thruster 2 fully described in our co-pending application and therefore not described in detail here. The thruster 2 is actuated by mechanical linkage 3 to press the Wall `of an inverted piece of prefabricated pottery Ware 4 against the con- The material remaining in the iilling hole 9 and the slit yI Il after the appendage rhas solidified forms a sprue I I, Fig. 7, which is attached tothe underside of the appendage by a portionV I2 of low mechanical strength or a weakened portion. When the sprue is detached,.it will break throughV the weakened portion at substantially the level of the surface of the appendage or slightly thereabove, as illustrated in Fig. 8.

pit orY cavityl therein which cannot be repairedy or erased by sponging. Considerable ware is rendered second or third grade by becoming pittedl in the'manner described and while the pit is in a concealed location, it nevertheless is discernible when the cup is raised. l

The slit I0 at the bottom of the hole 9 preferably communicates'with the molding cavity at the uppermost zone thereof in order that air ven- Vtrapment will be minimized and complete lling of the mold assured. Oi course, in actual practice, the' seal between the wall of the ware and the contoured'surface 5l of the mol-d is not en- If a 'slightI prominence I4 remains onthe appendage, this' 4 primarily responsible for filling the cavity to its' limit and driving out the air.

The mold of Figs. 4, 5 and 6 is made up of separable sections each of which has hinge formations 20 with grooves 2l to t the hinge pin 1. A

Y Spring Clip- 22, Fig. 11, may be used to clamp the sire to be limited to this specic shape or form Y of gate illustrated. The dimensions of the gate should be such that it will not clog as long as the clay slip will flow. Of course, when the material solidies, all flow through the gate ceases. bond between the sprue and appendage should The f also be strong enough to support-l the weight of waste material forming the sprue when the mold' is opened. Sometimes the sprue has a liquid center and premature breakage would spatter the ware which is not desired.

The sprue may be removed from the Vappendage by knocking it sdewise along the line of juncture' with the appendage, Fig. 8, or it may be pinched lightly between the thumb and index linger and twisted.

A method of removing the sprue without touching the same with the fingers is to grasp lthe cup securely in one hand while it rests on the support I and then lift it clear and snap off the sprue by flipping the cup and then abruptly halting it. This causes the sprue to snap off of its own momentum across the weakened portion. This is usually done over a receptacle into which the waste material is thrown. This method speeds up the process of removing the sprue by eliminating excess manual handling.

In Figs. 4, 5 and 6 is Yshown a separable mold having a pouring hole I5 of globular or spherical shape whose inlet I6 may be circular or elliptical. This form of pouring hole produces a` sprue of balanced design less apt to crackoff prematurely when the mold is opened. Furthermore, being of globular or spherical shape, there are no crevices or sharp corners for the clay to stick in and the .clay slip in the cavity will tend to shrink uniformly from theV wall thereof. Having an inlet I B which is small in proportion to the area of the hole I5, only a small portionV of the contents is;

exposed to atmosphere. This retards setting up in the sprue before the Yappendage solidies.

It will be understood that the wall of .the holes 9 or I5 may be treated or impregnated with oil,`

wax, gum, shellac or other preparation which will retard the absorbtive characteristics of the plaster of which the wall is formed in order lthat the sprue will remain iluid longer than the appendage'` and thus capable of supplying additional materiali` to the appendage cavity as solidiflcation sets in.

This treatment may also be administered tothe Walls of the gate 9 or slit I'I, Fig. 5, which isy formed at the bottomKof a passage I8 communi-l cating with the spherical hole I5. The sprue thus formed has the shape of aball supported on a stem attached -to the appendage by a weakened portion as at I 2, Fig. 7. The lower wall I9 of the passage I8 preferably tapers into the slit. TheV The volume of clay slip which .thea

mold sections together. lThis type of-mold may be used with automatic mold opening and closing machinery or may be opened by hand if provided with the friction roller devices 23 or similar appurtenances such as illustrated in connection with the mold of Fig. 11 which stand out at an angle from the body of each section on opposite sides of the mold and are adapted to be engaged and pressed toward one another :to spring the mold open in an obvious fashion.

In the mold ofrFigs. l0 and 11, the same general principles of construction of the pouring hole and gate are retained, however, the pouring hole 24 herein is enlarged and cylindrical or elliptical in shape and may taper toward the' base or may have a straight side if desired, The bottom of the hole has a pronounced taper as at 25 leading into the slit or gate 2B to the molding cavity. In this form of pouring hole, the gate is directly below the pouring hole whose gate is near the top of the molding cavity. Otherwise, the mold is the same as that shown in Figs. 4, 5 and 6, and is notched out at 25 at the rear around the hinge pin in or-der that the sections may pivot Yon the pin.

, Thus, the present invention also contemplates a. method of appendaging' pottery ware wherein the mold and prefabricated ware are rst brought together with the outlet 26 facing the wall of the cup and then slip is poured or piped into the pouring hole and discharged into the cavity through a reduced inlet or passage toy form an appendage having a sprue attached thereto by a weak portion. After the appendage is solidified, the sprue is Vdetached by breaking it oif,'the .Weak portion giving way and permitting a clean separation substantially flush withpthe surface of the appendage. Y Y l Figure 9 shows a mold section Vrepresentative Y of any one of those previously described wherein the hinge formations Zumay beomitted and a metal backing 28 with a hinge formation 29,-substituted therefor. This type of composite Ymold is shown in Fig. l and the two piecesv ofjthesection may be joined by casting the plasterportion on the metal portion. When the plaster wears out, it is simply knocked off and a new plaster section cast on the hinge plate. 'Obf edge at they juncture of Vthe sprue with the ap-Z pendage. The object is to insure that the sprue will break oif above Vthe surface of the appendage` and not tear a hole in the appendage., It will be understood that the fillet may or may n ot be employed,4 as desired., -f Y i Y In snapping olf the sprue withoutftouching itrby hand, the factor oir-inertia is involved due to the property of the sprue to continue its motion and snap off when the motion of the ware is arrested. Therefore, we prefer to refer t0 off'by inertia.

Having thus claim is: -f v l. A mold for casting an appendage on pre-' fabricated potteryware comprising, a .se-parable describedV our invention, what we 5 body having a ware engaging surface contoured to t the exterior surface of the ware, a molding cavity in which the appendage is formed having an outlet through the ware engaging surface and a pouring passage through which casting slip is poured into the molding cavity formed for producing a waste piece joined to the appendage -by an elongated neck that is substantially narrower than either the appendage or the waste piece and provides a rupture area having less resistance to breakage than either the appendage or the waste piece.

2. A mold for casting an appendage on prefabricated potteryware comprising, a separable body having a ware engaging surface contoured t0 fit the exterior surface of the ware, a molding cavity in which the appendage is formed having an outlet through the ware engaging surface and a pouring passage through which casting slip is poured into the molding cavity formed for producing a waste piece joined to the appendage by an elongated neck along the seam line between mold sections that is substantially narrower than either the appendage or the balance of the waste piece and may be broken off flush or immediately above the surface of the appendage when pressure is exerted on the Waste piece across the narrow dimension.

3. A mold for casting an appendage onk prefabricated potteryware comprising, a separable 6 body having a ware engaging surface contoured to t the exterior surface of the ware, a molding cavity in which the appendage is formed having an outlet through the ware engaging surface and a pouring passage through which casting slip is poured into the molding cavity formed ware, the method which comprises slip casting an appendage against the exterior surface `of the prefabricated ware and forming a waste piece joined thereto by an elongated neck that is substantially narrower than the appendage or the remainder of the waste piece, the waste piece above the neck having suicient mass to cause it to snap off by inertia and, after the cast has been made, removing the ware with the appendage and waste piece attached thereto from the mold and moving the ware in such a manner as to break the restricted neck across the narrow dimension by the inertia of the waste piece.

WILLIAM J. MILLER.

ASHLEY J. REEK. 

